Parallelogram-type pantograph



- Ap il 2, 19,29. TuPQLAMP v 1,707,914

' PARALLELOGRAM TYPE PAN' I'O'GRAP-H Filed v- 1924 5 Sh eets-Sheet 1 Inventor:

Thorwa'ld 'P. Lampg AprilZ, 1929; T P. LAMPE 1,707,914

I PARALLELOGRAM TYPE P'ANIIOGRAPH Filed Nov. 5, 1924' 5 Sheets-Sheet 2 &, LL

1 Inventor.

Thorwald P. Lampe April 2, 1929. p LAMPE 1,707,914

PARALLELQGRAM TYPE PANTOGRAPH Filed ov- 5, 1924 S Sheets-Sheet 4 I mzentor:

a: Thorwald P.'Lampe Patented Apr. 2, 1929.j

THOR-WALD I. LAMPE, OI WASBINGTON, DISTRICT OF COLUMBIA.

PABALLE LOGRAM-TYPE 'I'OGB-LPH.

Application filed November 3, 1924. Serial No. 747,618.

My invention relates to any pantograph and has for an object the provisionof an efiicient means for the reproduction of lines, letters or symbols.

Another object of my invention is to provide a pantograph which may be operated by one not skilled in the art.

Another object of my invention is to provide a means for increased accuracy, in delineation of chart or map features in their true position. j

A further object of my invention is to providea device whereby efiiciency in chart and map engraving is increased by the elimination of a large amount of work necessarily involved in the preparation of drawings and prints to the scale of engraving.

A still further object of my invention is to provide a device by which the output is increased and the cost reduced.

With these and other objects in view my invention will be best understood by refer ence to the accompanying drawings in which Figure lis a perspective view of my invention. Figure 2 is a front elevation. Figure 3 is a plan view. Figure 4 is an elevation in detail. Figure 5 is a section showing details of Figure 4. Figure 6 is a side view of the weight control lever. Figure 7 is a side view of the producing point control lever. Figure 8 is a plan view of Figure 6. Figure 9 is a section on the line 99 of Figure 6. Figure 10 is a section on the line 10-10 of Figure 9. Figure 11 is a plan view of the adjustable joints. Figure 12 is a section on the line 1212 of Fi ure 11.

Referring particularly to igures l and 2, the table 1 is the basesand support for my invention and is ofrigid construction, preferably of steel with a wooden top, the table .being adjustable to a horizontal plane by any suitable means such as screw jacks 13 preferably built in the legs of the table 1.

Fourarms 2, 3i 4 and 5 are assembled upon a principle simi ar to that of any reducing pantograph consisting of an anchor point 75 and tracing point 74, said arms being supported above and parallel to the table 1 by means of an adjustable anchor post 14" and adjustable guys 15 and 16. A compensating device, shown in Figure 3, consists of an arm 6 attached to connecting arms 7 and 8 which form an' auxiliary pantograph, a pivot point 9 adjustable in slotted rails 10, and a movable copy board 11 connected with the arm 6 by means ofan adjustable connecting rod 12. N 0 claim is made for the com ensating device or the movable copy board this feature being covered b Patent 1,695,381, Dec. 18, 1928 to John H. liarrabee.

parallel to the table 1 by brackets 17. v

The arm 3 of the pantograph isconnected The rails 10 are supported above and at its ends to arms 4 and .5 by the ball bearing joints 19 which are movable in thecarriages 18, as illustrated inFigures 3 and 11. The joint is made concentrically with the ,axis of the connected arms. The carriages 18 are clamped onthe arms 4 and 5 by clamps 20 and are provided with a vernier (not shown) and a slow motion screw 21, whereby the position and adjustment of the carriages are determined and set'in the slots 23. Arms 3, 4 and 5 each carry a graduated scale 22,

shown in Figure 4, divided into decimal parts of the length of the arm, except in arm 4, the divisions of which with those of arm 5. This decimal subdivision allows direct setting of the pantograph for any ratio of reduction within the scripe of the particular instrumentin use.

correspond teferringparticularly to Figures 3, 4 and A 5, on arm 3, adj ustably and movably attached and adapted to. slide in slot 24 is a carriage 25. Passing through the center of this carriage is ani opening 26 vertical to the plane of the table through ,vvhich an adjustable cutting point 27 is, passed. Carriage25 is adapted to slide in slot 24, the position being determined by meansof scale 22 and vernier 28 attached to the carriage by a means such as the screws 29. 'When the proper position ofcal'riage 25' is determined it may be securely clamped in position by clamping screws 30 and 31. A still finer vadjustment of the carriage is made'possible by means of a clamping screw 34 and a slow motion screw' 32 which threads into frame 33, frame 33 being securely attached to carriage,25

The pulleys 35, 36 and 37,]whichserve as guides for means 38 are fitted to frame 33. Means 38 regulates the pressure applied to cutting point 27 and is attached to shaft 39. Said shaft so tapers and is provided with shoulders on which' rest the weights 41, which determine the pressure independently raised or lowered, thereby varyin the pressure on the cutting point 27. T e upper portion 42 of the cutting.

point engages in a recess of shaft 39, serving as a guide therefor. Lever 43, operated by means 47, moving on pivot point 44, and forked at its outer end, is adapted to lift cutting point 27 clear of the workmaterial 46upon which work is being produced; 'Spring serves to hold lever 43 away from cup 40 when the cutting point is in an operative position.

A means for operating the weights 41 is illustrated in Figures 6, 8, 9 and 10 and consists of a lever 48 pivoted adjacent the end of arm 5, operating over a. segment 49 which is provided'with an upturned edge 50, this edge having openings 51 there through. The lever carries a locking member 52 successively engageable in theopen- 'ings and held in locked position by a spring 53 within the lever and engaging against a plunger 54 carrying said lockingmember. To release said member from an o ening, pressure is exerted on the plunger t irough a thumb piece 55 intrically formed therewith. Thelever is connected to means 38 through a turn-buckle 56 which permits adjustment of the tension in the entire weight control means. In orderto provide a means for lifting and lowering the cutting point 27 I have employed, as illustrated in Figure 7, a slid able and rotatable member 57, manually operated, said member 57 sliding on tracing point shaft sleeve 76. Member 57 contains a slotted groove 59, which engages the rounded head 60 of lever 61, pivoted at point 62 to the arm 5. Lever 61 is of the bell: crank type and is connected to means 47 through a turn-buckle 63. To lift the cutting point 27, member 57 is moved .downward on tracing point shaft sleeve 76. In 5 order to lock the cutting point in this position I have provided a pin 64 attached to member 57. By rotating said member while in its downward position, pin 64 is brought to bear on the under surface of the end of arm 5 thereby locking the cutting point in its inoperative position. To lower the cutting point this operation is reversed. Figure 7 I shows member 57 in the up position corresponding to the position of the cutting 66 rigidly attached to'table l and preferv ably at the corner illustrated. It is to be understood that. this stanchion may be lo .cated at any corner of the table or at a point outside the table. The boom 67 is rotatably' attached to the stanchion 66 ad- ,jacent to its upper extremity, as 9.568,

by means of a joint, preferably. one of a ball bearing type. The boom is held and supported in a horizontal position by means of the adjustable guy 69. Slidabl attached.

to theboom 67 is a carriage '70, tted with ball bearing roller 71. The carriage 70 is connected to the arm 5 by means of'a spring 72 and an adjustable hook 73, said book by means of ajscrew being adjusted in length thread attachment in the arm 5.

It will be understood that the above description and the accompanying drawings comprehend only the general and preferred embodiment of my invention and that various minor changes in details of construction, a

proportion, and arrangement of parts may claim without sacrificing any of the advantages of my invention.

Having described my invention what .I

claim is:

In'a pantograph arrangement comprisinging interconnected arms, a tracer and a reproducer carried by said arms, a'stem slidable along and guided by the reproducer,

weights disengageably supported by the stem, a cup secured to the reproducer, means adjacent the tracing point for moving the be made within the scope of the appended/ stem to cumulatively increase the pressure v on the reproducer by transferring the weights, from the stem'to the cup, and means adjacent the tracing point for raising and lowering the reproducer.

THORWALD P. LAMPE. 

